Washing machine level control



y 1963 J. w. JACOBS 3,095,895

WASHING MACHINE LEVEL CONTROL Filed Dec. 26, 1961 6 ale 0/; ar/

TIMER MOTOR OT FILL SOLENOID GOLD FILL SOLENOID WASHER MOTOR /8 Timer Sequence 3 I Energized TH Overf/awing while washing or soaking 62 f Overflow/0g while raising 52 3:6 33

' 72 D u I Fig INVENTOR. I James W Jacobs Fig. 2 22 His Af/omey United States Patent Office 3,095,895 Patented July 2, 1963 3,0953% WASHING MACHINE LEVEL CONTROL James W. Jacobs, Dayton, Ohio, assignor to General Motors Corporation, Detroit, Mich, a corporation of Delaware Filed Dec. 26, 1961, Ser. No. 161,796 Claims. (Cl. 137387) This invention relates to a domestic appliance and more particularly to an arrangement for insuring adequate water fill in a wash tub.

Every clothes washing cycle is preceded by a period of fill wherein water at a selected temperature is admitted to the washing tub or container. Some machines use float switches to terminate the fill period while others use a timed period of In the latter or timed fill arrangement, the quantity of wash fluid admitted to the wash tub depends upon water pressure at the fill valve being maintained above certain predetermined minimum values. Where the water pressure drops below that at which the fill valve is designed to operate, a. lesser quantity of wash fluid is admitted to the spin tub than is desirable for the washing cycle.

Accordingly, it is an object of this invention to provide means for insuring an adequate fill of water in a clothes tub supplied by a timed fill period.

Another object of this invention is the provision of thermostatic means selectively in series with the fill valves to the wash tub, said means being exposed to the fill fluid when said tub is full.

Another object of this invention is the provision of a spin tub in a water container, means for supplying water to said spin tub for a predetermined period and means in the drain line from said water container for extending said predetermined period until said spin tub overflows into said water container.

A more general object of this invention is the provision with a water container of a temperature responsive switch device in parallel with a timed water fill valve switch, said switch dew'ce acting to continue said fill period after said fill valve switch has been opened until said device is cooled by water reaching the proper level in said container.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein preferred embodiments of the present invention are clearly shown.

In the drawings:

FIGURE 1 is a side schematic view of a clothes washer suitable for use with this invention;

FIGURE 2 is a schematic wiring diagram for controlling the clothes washer of FIGURE 1 in accordance with this invention;

FIGURE 3 is a timer cycle chart illustrating the operation of the control circuitry of FIGURE 2 and the clothes washer of FIGURE 1; and

FIGURE 4 is another embodiment of this invention shown in a fragmentary portion of the wiring diagram of FIGURE 2.

In accordance with this invention and with reference to FIGURE 1, a clothes washer is illustrated. The clothes washer is formed with an outer cabinet 12 which encloses a fixed generally imperforate water container 14 and a vertically rotatably mounted spin tub 16. An agitator 18 is disposed within the spin tub and is connected to an agitating and spinning mechanism 20 below the water container 14 which includes a reversible motor 22 having a safety overload switch 23. When the motor 22 is rotated in one direction, the agitating and spin mechanism 20 is eflective to vertically reciprocate the agitator 18; whereas the reverse rotation of the motor 22 operates through the agitate and spin mechanism to rotate the spin tub 16 in a centrifuging or clothes wringing operation.

The spin tub '16 is of the open top variety which includes a plurality of overflow ports 24 circumferential'ly arranged about an upper portion thereof. Water may be supplied to the spin tub 16 by means of a chute 26 which is supplied by water at selected temperature from a hot water solenoid actuated valve 28 and a cold water solenoid actuated valve 30. When sutficient water is supplied to the spin tub 16, it overflows through the ports 24 and falls into the water container 14 from which it leaves by way of an outlet drain port 32, leading to a pump 34 and a remote drain line.

Control of the clothes washer 10 is accomplished through a timer 36 including a timer motor 37 which is housed in the control console 38 on the top of the washer.

In general and with reference to FIGURE 3, the clothes washing cycle controlled by the timer 36 includes a four minute period of wash fill followed by up to an eleven minute wash period of which two minutes is an overflow period during which water supplied to the tub is raised to the level even with the outflow ports 24. At this level the water overflows, carrying with it the lint and scum on the fluid surface before the motor 22 is reversed for the following two minute wash spin period. Next follows a six minute rinse fill period to supply the fluid to the spin tub 16 for a rinse period-the last three timer increments of which are devoted to overflowing the rinse water through the outflow ports 24. During the rinse period, the motor 22 is operated in a manner to cause the agitator 18 to reciprocate. After the rinse period, the motor 22 is again reversed to set up a centrifuging period wherein the spin tub 16 is rotated for five minutes to remove the moisture from the fabrics being washed. This series of operations is seen diagrammatically in the Operations Chart at the top of FIG- URE 3.

From the foregoing, it can be seen that the clothes washer 10 of this invention uses a timed fill period of four minutes at the start of a clothes washing cycle. Consequently, this invention will be explained with reference to the initial fill cycle, further details of the entire washi-ng cycle being adequately disclosed by the wiring diagram of FIGURE 2 in conjunction with the timer sequence of FIGURE 3.

The components included in the clothes washer .10 for controlling the fill period are a rinse temperature selector 40 having a switch 42 which, in its open position (timer contact I closed), prescribes a Hot rinse only and which, in its closed position, prescribes a Warm rinse. In addition to the rinse selector 42, there is a wash temperature selector 44 operable on the control console 38 which includes two switches 46 and 48. When both switches 46 and 48 are closed (timer contact H closed), the wash water will be Warm; when the wash. selector switch 46 is open and the wash selector switch 48 is closed, there will be a Hot wash; and lastly when the switch 48 is open and the switch 46 is closed, there will be prescribed a Cold wash. Completing the components devoted to the fill period is a negative temperature coeflicient device, such as a thermistor 50 which is disposed in the drain outlet 32 of the water container 14 or, more generally, in thermal transfer relationship to water draining from the container. The thermistor S0 is in a position to be inundated by any fluids passing from the water container to the drain. It is this thermistor 50 which insures that suflicient fill is provided for the spin tub 16, when the water pressure at the hot or cold solenoid actuated valves is too low to admit the desired quantity of water in the predetermined four minute fill period.

Turning now to FIGURE 2, a clothes washing cycle is started when a timer dial- 52 is rotated to the start position and depressed to close the push-pull start switch 54. The rotation of the timer dial closes the timer contacts A, B, D, F and H. Thus, with thewash selector switch 44 shown as in FIGURE 2, the hot water solenoid 28 will be energized from L through the On/Ofl switch 54, the timer motor switch 56, the conductor 58, timer switch .60, conductor 62, wash selector switch 48 to the other side of the line L At the same time, the cold water solenoid 30 will be energized from the conductor 62 through the wash selector switch 46, the timer switch 64, the conductor 66 tothe other side of the line. Warm wash wateris-now being supplied through the chute 26 to the spin tub- 16. The fill period will continue for four minutes as shown inthe cycle chart. At the end of four minutes, the timer switch 60 will open the contact F and close the contact G, thereby interrupting the timer circuit to the Water fillv solenoids 28 and '30. At this time, the closing of the contact G energizes the motor 22 in accordance with the positioning of the reversing switches 70 and 72.

Let us-assumethat insuflicient water has been supplied the spin tub 16 to perform an adequate clothes washing operation. In other words, insufficient water has been supplied to bring thewater level in the tube 16 up to the overflow ports 24. The thermistorh-as been shunted throughout the period of time that the timer switch 60 was engaged on contact F and starts to heat when the switch 60 moves from F to G. When the thermistor is heated, it will provide a low resistance path'for current to continue to supply theselected water solenoids 2S--and/or 30. In this regard, thesolenoids are relatively high in resistance so a load resistor '74, connected to the other sideiof the line 'as at 75, permits enough current to flow through the thermistor to make it self-heating. Thus, the fill period continues with the sole'noids beingenergized through the thermistor 50 As soon as water overflows the tube 16 by way of the outflow ports 24, this water will flow over the thermistor S in the drain port 32,; thereby to-cool the thermistor.- As the thermistor cools, its resistance raises so that current to the'solenoid falls oli and the solenoids close thereby terminating the fill period with anadequate supply of water inthe spin tub.

Another embodiment of this invention is shown 'in FIGURE4 wherein a bimetal thermostatic device 80 is shown adapted for incorporation into the circuitry of FIGURE Z. The thermostat 80 includes a normally open bimetal switch 82 as a single pole, single throw switch connected in shunt across the timer contact P which energizes the water solenoids during wash'fill. The thermostat 80 has a built-in 'heat'er'84 connectedto heat the bimetal '82 and keep theswitch closed as a locked-in relay until overflow of water from the wash tub chills the bimetal and opens the contact 86. This heater 84 is connected iii-parallel with the hot water solenoid 28. As with the thermistor embodiment, the thermostat 80 will act to extend the fill period until water overflows the tub and cools the bimetalthe bimetal being disposed in heat exchange relationship to water flowing through the drain outlet 32.

It should now be seen that an improved method has been provided for insuring adequate water fill in a washing machine provided with timed fill.

While the embodiments of the present invention as herein disclosed constitute preferred forms, it is to be understood that other forms might be adopted! What is claimed is as follows;

1. In combination, means forming a wash tub having an outflowport in an upper portion thereof, means including a solenoid actuated valve for supplying water to said wash tub, timer means for energizing said solenoid actuated valve for a predetermined time whereby said valve is conditioned to supply a predetermined quantity of water to said Wash tub to a level even with said outflow port, and thermistor means in parallel with said timing means and ing heat exchange relationship with water flowing from said outflow port for continuing the energization of said solenoid actuated valve for an additional period necessary to insure a fill of water to said predetermined quantity.

2. In combination, means forming a wash tub'having an outflow port in an upper portion thereof, means including a solenoid actuated valve for supplying water to said wash tub, timer means for energizing said solenoid actuated valve for a predetermined time whereby said valve is conditioned to supply a predetermined quantity of water to said wash tub to a level even with said outflow port, heater means in series with said timer means, and normally open heat closable bimetallicnswitch means in parallel with said timingmeans and in heat exchange relationship with said heater means and with water flowing from said outflow port for continuing the energization of said solenoid actuated valve for an additional period necessary to insure a fill of water to said predetermined quantity.

3. In combination, means forming a container having an overflow port, means including an electrically actuated valve means forsupplying water to said container, timer means closable for energizing said valve means for a predetermined time whereby'said valve means is conditioned to supply a predetermined quantity of water to said container and said overflow port, and temperature responsive switch-means in parallel with said timing means and in series with said valve means and closable prior to the opening of said timer means, said temperature responsive switch means located in heat exchange relationship to water flowing from said overflow 'port for continuing the energization of said valve means for an additional period necessary to insure a fill of water to said predetermined quantity.

4. In combination, means forming a container having outlet means, means including an electrically actuated valve for supplying fluid to said container, first control means for energizing said electrically actuated valve for a predetermined time whereby said valve is conditioned to supply a predetermined quantity of fluid to said con tainer to a level even with said outlet means, and temperature responsive second control means in parallel with said first control means and in heat exchange relationship with fluid flowing from said outlet means for continuing the energization of said electrically actuated valve for an additional period necessary to insure a fill of fluid to said predetermined quantity.

5. In combination, means forming a vertical spin tub having overflow means, means including an electrically actuated valve for supplying fluid to said spin tub, first control means for energizing said electrically actuated valve for a predetermined time whereby said valve is conditioned to supply a predetermined quantity of fluid to said spin tub to a level even with said overflow means, and fluid contact responsive second control means in parallel with said first control means and in contact relationship with fluid overflowing the spin tub from said overflow means for continuing the energization of said electrically actuated valve for an additional period necessary to insure a fill of fluid until said fluid overflows said spin tub and contacts said second control means.

References Cited in the file of this patent UNITED STATES PATENTS 2,353,042 Koch July 4, 1949 2,896,436 Buechler July 28, 1959 2,986,915 Nau June 6, 1961 

1. IN COMBINATION, MEANS FORMING A WASH TUB HAVING AN OUTFLOW PORT IN AN UPPER PORTION THEREOF, MEANS INCLUDING A SOLENOID ACTUATED VALVE FOR SUPPLYING WATER TO SAID WASH TUB, TIMER MEANS FOR ENERGIZING SAID SOLENOID ACTUATED VALVE FOR A PREDETERMINED TIME WHEREBY SAID VALVE IS CONDITIONED TO SUPPLY A PREDETERMINED QUANTITY OF WATER TO SAID WASH TUBE TO A LEVEL EVEN WITH SAID OUTFLOW PORT, AND THERMISTOR MEANS IN PARALLEL WITH SAID TIMING MEANS AND ING HEAT EXCHANGE RELATIONSHIP WITH WATER FLOWING FROM SAID OUTFLOW PORT FOR CONTINUING THE ENERGIZATION OF SAID SOLENOID ACTUATED VALVE FOR AN ADDITIONAL PERIOD NECES- 